Re: pqReadData() -- backend closed the channel unexpectedly. - Mailing list pgsql-general

Ouch, 12 megs of RAM with FreeBSD *might* lead to troubles itself.

From
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/install-hw.html :

"In order to run FreeBSD, a recommended minimum of eight megabytes of RAM is
suggested. Sixteen megabytes is the preferred amount of RAM as you may have
some trouble with anything less than sixteen depending on your hardware.."

I can't decipher anything from the log but hopefully someone else can to
tell you if it's a memory problem or not for sure (if it is, I'd think PG
would exit a bit more gracefully)...

Good luck!

-Mitch

----- Original Message -----
From: "Lee Harr" <lee@troll.east.rochester.k12.ny.us>
To: <pgsql-general@postgresql.org>
Sent: Monday, July 23, 2001 10:19 AM
Subject: [GENERAL] pqReadData() -- backend closed the channel unexpectedly.


> I am running PostgreSQL 7.1.2 on FreeBSD 4.3
> This is an old 486 with only 12MB memory.
>
> I am able to create databases and insert and retrieve data,
> but when I try to query on the structure of the database
> I am getting this error:
>
> signin=# \d person_personid_seq
> pqReadData() -- backend closed the channel unexpectedly.
>         This probably means the backend terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.
> !# \q
>
>
> I have never seen that prompt before (!#)
>
> I turned up debugging and here is (some) of the output:
>
> <snip>
> DEBUG:  database system is in production state
> DEBUG:  proc_exit(0)
> DEBUG:  shmem_exit(0)
> DEBUG:  exit(0)
> postmaster: reaping dead processes...
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> <snip>
> postmaster: ServerLoop:         handling writing 4
> postmaster: BackendStartup: pid 635 user lee db lee socket 4
> postmaster child[635]: starting with (postgres -d5 -d 5 -v131072 -p lee )
> FindExec: searching PATH ...
> FindExec: found "/usr/local/bin/postgres" using PATH
> DEBUG:  connection: host=[local] user=lee database=lee
> DEBUG:  InitPostgres
> DEBUG:  StartTransactionCommand
> DEBUG:  query: SELECT usesuper FROM pg_user WHERE usename = 'lee'
> <snip>
> DEBUG:  ProcessQuery
> DEBUG:  CommitTransactionCommand
> DEBUG:  proc_exit(0)
> DEBUG:  shmem_exit(0)
> DEBUG:  exit(0)
> postmaster: reaping dead processes...
> postmaster: CleanupProc: pid 635 exited with status 0
> postmaster: ServerLoop:         handling reading 4
> <snip>
> postmaster: ServerLoop:         handling writing 4
> postmaster: BackendStartup: pid 642 user lee db signin socket 4
> postmaster child[642]: starting with (postgres -d5 -d 5 -v131072 -p
signin )
> FindExec: searching PATH ...
> FindExec: found "/usr/local/bin/postgres" using PATH
> DEBUG:  connection: host=[local] user=lee database=signin
> DEBUG:  InitPostgres
> DEBUG:  proc_exit(0)
> DEBUG:  shmem_exit(0)
> DEBUG:  exit(0)
> postmaster: reaping dead processes...
> postmaster: CleanupProc: pid 639 exited with status 0
> <snip>
> postmaster: reaping dead processes...
> postmaster: CleanupProc: pid 642 exited with status 132
> Server process (pid 642) exited with status 132 at Mon Jul 23 09:46:26
2001
> Terminating any active server processes...
> Server processes were terminated at Mon Jul 23 09:46:26 2001
> Reinitializing shared memory and semaphores
> invoking IpcMemoryCreate(size=1236992)
> DEBUG:  database system was interrupted at 2001-07-23 09:44:48 EDT
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> The Data Base System is starting up
> postmaster: ServerLoop:         handling writing 4
> DEBUG:  CheckPoint record at (0, 3580356)
> DEBUG:  Redo record at (0, 3580356); Undo record at (0, 0); Shutdown TRUE
> DEBUG:  NextTransactionId: 1362; NextOid: 101105
> DEBUG:  database system was not properly shut down; automatic recovery in
progre
> ss...
> DEBUG:  ReadRecord: record with zero len at (0, 3580420)
> DEBUG:  redo is not required
> DEBUG:  database system is in production state
> DEBUG:  proc_exit(0)
> DEBUG:  shmem_exit(0)
> DEBUG:  exit(0)
> postmaster: reaping dead processes...
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> <snip>
> DEBUG:  StartTransactionCommand
> DEBUG:  query: SELECT relhasindex, relkind, relchecks, reltriggers,
relhasrules
> FROM pg_class WHERE relname='person_personid_seq'
> DEBUG:  parse tree: { QUERY :command 1  :utility <> :resultRelation 0
:into <> :
> <snip>
> <> :sortClause ({ SORTCLAUSE :tleSortGroupRef 1 :sortop 95 }) :limitOffset
<> :l
> imitCount <> :setOperations <> :resultRelations ()}
> postmaster: reaping dead processes...
> postmaster: CleanupProc: pid 654 exited with status 132
> Server process (pid 654) exited with status 132 at Mon Jul 23 09:47:37
2001
> Terminating any active server processes...
> Server processes were terminated at Mon Jul 23 09:47:37 2001
> Reinitializing shared memory and semaphores
> invoking IpcMemoryCreate(size=1236992)
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> postmaster: ServerLoop:         handling reading 4
> The Data Base System is starting up
> postmaster: ServerLoop:         handling writing 4
> DEBUG:  database system was interrupted at 2001-07-23 09:46:29 EDT
> DEBUG:  CheckPoint record at (0, 3580420)
> DEBUG:  Redo record at (0, 3580420); Undo record at (0, 0); Shutdown TRUE
> DEBUG:  NextTransactionId: 1362; NextOid: 101105
> DEBUG:  database system was not properly shut down; automatic recovery in
progre
> ss...
> DEBUG:  ReadRecord: record with zero len at (0, 3580484)
> DEBUG:  redo is not required
> DEBUG:  database system is in production state
> DEBUG:  proc_exit(0)
> DEBUG:  shmem_exit(0)
> DEBUG:  exit(0)
> postmaster: reaping dead processes...
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>